Willow Warbler

This tiny warbler has greenish-brown upper parts,
buff underparts and with a pale stripe above the eye. The Willow Warbler
is more yellow, has a longer supercilium and often (but not always) has paler legs
than the Chiffchaff. The bill is pale brown and the legs are dark brown to
flesh-coloured.

Closer inspection and a keen eye reveal that Willow Warblers also have longer wings and no eye-ring.

Key Differences between Chiffchaff and Willow Warbler

Legs

Wing

Eyebrow

Tail

Chiffchaff

Dark

Short

Short/Dull

Wags

Willow Warbler

Pale

Long

Long/Distinct

Flicks

In the autumn juveniles with fresh plumage can be very yellow looking.

Close-up

Singing

Scientific Name

Phylloscopus trochilus

Length

10-11.5 cm (4")

Wing Span

16-22 cm (6-9")

Weight

6-10 g (¼-½ oz)

Breeding Pairs

2300000

Present

Summer

Status

Amber

Voice

The best way of telling Willow Warbler and Chiffchaff apart is by their song.
The Willow Warbler's song is a melodic rippling phrase that rises quickly before
slowly dying away.

Their calls are almost identical, but in the autumn they rarely sing so the
call is often the easiest way of finding the warbler even if you cannot tell
them apart.

Feeding

Willow Warblers feed on insects, and are unlikely to visit bird
feeders. They are often seen fluttering at the ends of leaves and
branches; in fact, they are searching the undersides of the leaves for
aphids because this is where the aphids feed on the tree's sap.

Gardens with lots of shrubs that encourage
insects may entice Willow Warblers.

Nesting

The domed nest, made from grass, rotten wood, moss and roots, is on the
ground but among shrubs or grass. The nest has a side entrance and is
lined with fine roots and feathers.

The smooth, glossy white eggs are speckled with reddish-brown, and
approximately 15 mm by 13 mm. The female incubates the eggs by herself. After
the young hatch, they are fed by both parents.

Breeding Starts

Clutches

Eggs

Incubation (days)

Fledge (days)

April-May

1-2

3-9

13

13-16

Movements

Willow Warblers are summer visitors, appearing in the UK from about late March or early April
after having spent the winter in Africa, south of the Sahara.

Their migration is further than that of the Chiffchaff and this is why they
have slightly longer wings.

Conservation

The Willow Warbler has been placed on the Amber List of
species of conservation concern owing to recent decline in their numbers. The
most likely cause of this decline is deterioration in its wintering grounds
(Africa), but also changes in the management of woodland fringes in Britain.